Applied Biology

Question 1

What are some issues growers face with regard to plant nurseries?

Answer 1

Water/soil/light management, disease and pest control, nursery structures and environmental controls.

Question 2

What is defined as post-harvest loss?

Answer 2

Food loss that occurs along the food supply chain from harvesting to consumption

Question 3

Factors determining quality of harvest

Answer 3

When and how the harvest is done. Seed source and quality

Question 4

When can post-harvest losses occur?

Answer 4

During harvesting, handling, transport, storage, domestic processing and distribution

Question 5

Categories of post harvest losses

Answer 5

Weight loss due to spoilage, quality loss, nutritional loss, seed viability loss, commercial loss

Question 6

Results due to delay in paddy harvesting

Answer 6

Leads to all 5 types of losses. Enhanced losses if heavy rains occur right before harvesting.

Question 7

Results if paddy is harvested too early?

Answer 7

More moisture content leads to mold growth and insect infestations, leading to broken grains and low milling yield = COMMERCIAL LOSS.
More drying required, so higher drying cost.

Question 8

Results if fruits and vegetables are harvested too early?

Answer 8

Crop will not be matured enough

Question 9

Results if fruits and vegetables are harvested too late?

Answer 9

May spoil quickly, leading to quality and nutritional loss leading to ECONOMICAL LOSS.

Question 10

Consequences of mechanical damage occurring to fruits and veg when harvesting

Answer 10

Reduces quality and storage life since spoilage microbes will enter the crop through damaged areas.

Question 11

What is food preservation?

Answer 11

Process of treating and handling food to greatly slow down or stop food spoilage ( edibility, nutrition and quality loss ) caused or accelerated by microbes.

Question 12

What are the 3 principles of food preservation?

Answer 12

1. Prevent entry of microbes to food.
2. Killing or removing microbes on food
3. Prevent growth and activity of microbes on food.

Question 13

Principle behind drying. Give examples.

Answer 13

Mostly done in the sun. Reduces water activity of food sufficiently to reduce or prevent microbial growth.
Grains dried to increase shelf life, like corn, rice, oats.
Hams are meats preserved through oven-drying.

Question 14

What are stem cells?

Answer 14

Undifferentiated cells that are able to give rise to cells of the same type, and can divide mitoticallly without a limit and then terminally differentiate into different cell types.

Question 15

Requirement of stem cells

Answer 15

When there is a recurring need to replace differentiated cells that cannot divide themselves. Divide at a slow rate.

Question 16

2 main features of hESCs

Answer 16

1. Able to self renew indefinitely to produce more stem cells.
2. Able to differentiate into variety of different mature cells with specialized functions. UNDER PROPER GROWTH CONDITIONS.

Question 17

Pluripotent definition

Answer 17

Cells having the potential to divide and differentiate into variety of different cell types.

Question 18

How and when were iPSCs first formed?

Answer 18

Late 2006. Cells obtain from adult tissues from a donor were reprogrammed and pluripotent stem cells were derived from them.

Question 19

Advantages of using iPSCs

Answer 19

1. Bypasses the need for human embryos
2. Able to be made in patient- matched manner, each individual has their own line of iPSCs
3. Can propogate indefinitely.
4. Can give rise to every other cell type.
5. Provides a single source of cells to replace cells lost to damage or diseases.

Question 20

How is veg propogation using separation carried out?

Answer 20

Using naturally detachable plant parts like corms, rhizomes and bulbs.

Question 21

Examples for corms

Answer 21

Gladiolus, Alocasia, Colocasia

Question 22

What is referred to as tissue culture?

Answer 22

The ability to establish plant tissues ( cells, callus and protoplasts ) and plant organs (shoots, roots and embryos ) in an aseptic, in vitro culture.

Question 23

What are the features the farmers look for in seeds for sexual propagation of plants?

Answer 23

High quality seeds with higher percentage of germination, higher viability and free from damage due to pests and diseases.

Question 24

What does layering mean?

Answer 24

Rooting of stems while they are still attached to the parent plant.

Question 24

Plants in which self-layering occurs naturally as a form of regeneration

Answer 24

Cynodon grass species and strawberries

Question 24

Plants that can be propagated by LEAF cuttings

Answer 24

Sansevieria (SNAKE PLANT) , African violets, Begonia.

Question 24

What is done in the method of cuttings?

Answer 24

Generation of a new, fully developed plant from a piece of root, stem , leaf or leafy bud tissue.

Question 25

Plants that can be propagated by cuttings.

Answer 25

African violets, Roses, Ficus, Dracaena, Croton.

Question 25

What are adventitious roots?

Answer 25

Roots arising from stem, leaf or bud tissue.

Question 25

Plants in which layering is carried out

Answer 25

Roses, Hibiscus

Question 26

What is known as grafting? Give an example for a plant in which it is used.

Answer 26

Joining of 2 separate plants so that they will later function as a single healthy plant. Roses.

Question 27

How to minimise losses at the stage of domestic processing?

Answer 27

By minimising losses at the previous stages, by harvesting crops at the appropriate times, hygienic handling to prevent contamination, and proper storage.

Question 28

How do we minimise transport losses due to poor road infrastructure and poorly maintained transport modes?

Answer 28

By having well planned, better modes of transport WITH AN EFFICIENT BULK HANDLING SYSTEM.